Buggy code:
public class ClipCardsPlayer implements TextureView . SurfaceTextureListener { public final String TAG = getClass ( ) . getSimpleName ( ) ; protected Context mContext ; protected FrameLayout mContainerLayout ; protected List < ClipCard > mClipCards ; private ArrayList < Integer > accumulatedDurationByMediaCard ; protected ClipCard mCurrentlyPlayingCard ; protected MediaPlayer mMainPlayer ; protected MediaPlayer mSecondaryPlayer ; private Uri mSecondaryAudioUri ; private Surface mSurface ; protected ImageView mThumbnailView ; private TextureView mTextureView ; private SeekBar mPlaybackProgress ; private Timer mTimer ; protected Handler mHandler ; private boolean mAdvancingClips ; protected boolean mIsPlaying ; private boolean mIsPaused ; private int mCurrentPhotoElapsedTime ; private int mPhotoSlideDurationMs = 5 * 1000 ; private int mClipCollectionDurationMs ; private final int TIMER_INTERVAL_MS = 100 ; private OnClickListener PlaybackClickListener = new View . OnClickListener ( ) { @ Override public void onClick ( View v ) { } } ; protected static class ClipCardsPlayerHandler extends Handler { public static final int START = 0 ; public static final int RESUME = 1 ; public static final int PAUSE = 2 ; public static final int STOP = 3 ; public static final int ADVANCE = 4 ; public static final int RELEASE = 5 ; public static final int TIMER = 6 ; private WeakReference < ClipCardsPlayer > mWeakPlayer ; public ClipCardsPlayerHandler ( ClipCardsPlayer player ) { } @ Override public void handleMessage ( Message msg ) { } } public ClipCardsPlayer ( @ NonNull FrameLayout container , @ NonNull List < ClipCard > clipCards ) { } public void setPhotoSlideDurationMs ( int durationMs ) { } public void addAudioTrack ( MediaFile mediaFile ) { } private void init ( ) { } private void setupViews ( @ NonNull FrameLayout root ) { } private void setupTimer ( ) { } private void onTimerTick ( ) { } private void _onTimerTick ( ) { } @ Override public void onSurfaceTextureAvailable ( SurfaceTexture surfaceTexture , int width , int height ) { } @ Override public void onSurfaceTextureSizeChanged ( SurfaceTexture surface , int width , int height ) { } @ Override public boolean onSurfaceTextureDestroyed ( SurfaceTexture surface ) { } @ Override public void onSurfaceTextureUpdated ( SurfaceTexture surface ) { } protected void advanceToNextClip ( MediaPlayer player ) { } protected void _advanceToNextClip ( MediaPlayer player ) { } protected void _advanceToClip ( MediaPlayer player , ClipCard targetClip , boolean autoPlay ) { } protected void startPlayback ( ) { } protected void _startPlayback ( ) { } private void pausePlayback ( ) { } private void _pausePlayback ( ) { } private void resumePlayback ( ) { } private void _resumePlayback ( ) { if ( ( ( mMainPlayer ) != null ) && ( ! ( mMainPlayer . isPlaying ( ) ) ) ) { mMainPlayer . start ( ) ; } <START_BUG> if ( ( ( mSecondaryPlayer ) != null ) && ( mSecondaryPlayer . isPlaying ( ) ) ) { <END_BUG> mSecondaryPlayer . start ( ) ; } mIsPaused = false ; mIsPlaying = true ; } protected void stopPlayback ( ) { } protected void _stopPlayback ( ) { } private void release ( ) { } private void _release ( ) { } protected void prepareMainMediaPlayer ( MediaPlayer mainPlayer ) { } protected boolean firstClipCurrent ( ) { } protected void setThumbnailForClip ( @ NonNull ImageView thumbnail , @ NonNull ClipCard clipCard ) { } private void setClipExampleDrawables ( String clipType , ImageView imageView ) { } private int calculateTotalClipCollectionLengthMs ( List < ClipCard > cards ) { } private void adjustAspectRatio ( TextureView textureView , int width , int height ) { } }

Fix:
if ( ( ( mSecondaryPlayer ) != null ) && ( ! ( mSecondaryPlayer . isPlaying ( ) ) ) ) {